Method of manufacturing a last

ABSTRACT

A method of manufacturing a last for a first article of footwear. The last comprising a cast shaped and dimensioned to customize, in use, one end of the first article of footwear for one end of an individual&#39;s foot, and an end piece adapted to engage, in use, the opposite end of the first article of footwear. The method comprising the steps of customizing the cast and fixing the cast.

This application is a 371 of PCT/EP96/02786 filed on Jun. 21, 1996.

TECHNICAL FIELD

The present invention relates to a method of manufacturing a last for anarticle of footwear and a last for an article of footwear. The term"last" as used herein is intended to embrace both a shoemaker's modelfor making, shaping and/or repairing an article of footwear and a shapedblock or shoe-tree for shaping or maintaining in shape an article offootwear. The present invention has particular application in the fieldof customised articles of footwear.

BACKGROUND ART

GB-A-765,371, discloses a method of making shoe-trees in which a platercast is made of the front part of an individual's foot and fixed to anend piece to form a shoe tree. Such a shoe tree suffers the disadvantagethat the plaster cast reflects the shape of the external surface of theindividual's foot when the foot is not restrained by an article offootwear. Since much of contemporary fashion footwear causes anindividual's foot to be deformed to some extend, a shoe-tree formed inaccordance with GB-A-765,371 would not necessarily be insertable in suchfashion footwear.

GB 476,323 discloses a method for making an orthopaedic last derivedfrom an orthopaedically correct old shoe, from which last anorthopaedically correct arch of a new shoe can be subsequentlymanufactured. The orthopaedic last is formed by filling theorthopaedically correct old shoe with a plastic material and allowingsaid material to set. Such a method suffers from the disadvantage thatit can only be performed using old shoes whose bodies do not comprisestraps or apertures since such footwear could not contain the un-setplastic material. The methods of GB 476, 323 would not therefore besuitable for many styles of contemporary fashion footwear.

DISCLOSURE OF THE INVENTION

According to the present invention there is provided a method ofmanufacturing a last for a first article of footwear, the lastcomprising a cast shaped and dimensioned to customise, in use, one endof the first article of footwear for one end of the individual's foot;and an end piece adapted to engage, in use, the opposite end of thefirst article of footwear, said method comprising the steps ofcustomising the cast for said one end of the individual's foot; andfixing the cast to the end piece.

Preferably, the customising step comprises forming the cast from theinternal surface of one end of a second article of footwear.

Alternatively, the customising step comprises forming a mould of theexternal surface of one end of the individual's foot; and forming thecast from the mould.

Preferably, the cast is formed by lining the internal surface of one endof the second article of footwear; and filling the lining with amaterial which is suitable for forming the cast.

Further preferably, the lining is formed from latex rubber or the like.

Advantageously, the method additionally comprises the step ofcustomising the end piece for the opposite end of the individual's foot.

More advantageously, the customising step comprises forming the endpiece from the internal surface of said opposite end of the secondarticle of footwear.

Even more advantageously, the end piece is formed by lining the internalsurface of said opposite end of the second article of footwear; andfilling the lining with a castable material.

Alternatively, the customising step comprises forming a mould of theexternal surface of the opposite end of the individual's foot; andforming the end piece from the mould.

According to a second aspect of the invention, there is provided a lastfor a first article of footwear, the last comprising a cast shaped anddimensioned to customise, in use, one end of the first article offootwear for one end of an individual's foot; an end piece adapted toengage, in use, the opposite end of the first article of footwear; andmeans for fixing said cast to said end piece.

Preferably, the cast conforms substantially to the shape of the internalsurface of one end of a second article of footwear.

More preferably, the end piece conforms substantially to the shape ofthe internal surface of the opposite end of the second article offootwear.

Even more preferably, the internal surface of the second article offootwear has been pre-shaped by the individual's foot through wear.

Alternatively, the cast conforms substantially to the shape of theexternal surface of one end of the individual's foot.

More advantageously, the cast is made from a mould of the externalsurface of said one end of the individual's foot.

Even more advantageously, the end piece conforms substantially to theshape of the external surface of the opposite end of the individual'sfoot.

Still more advantageously, the end piece is made from a mould of theexternal surface of said opposite end of the individual's foot.

Preferably, the cast is formed from polyester resin or the likematerial.

More preferably, the end piece is formed from polyester resin or thelike material.

Even more preferably, the mould is formed from fiberglass or the likematerial.

Further preferably, the fixing means comprises resilient means arrangedto urge, in use, the cast and the end piece into engagement with thefirst article of footwear.

BRIEF DESCRIPTION OF THE DRAWINGS

Two embodiments of the invention will now be described, by way ofexample, with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a last according to the invention; and

FIG. 2 is a perspective view of an alternative last;

FIG. 3a is a perspective view of a second article of footwear into whicha lining is partially inserted;

FIG. 3b is a perspective view of the second article of footwear in whichthe lining is being filled with a castable material.

FIG. 3c is a perspective view of a first article of footwear into whicha last is partially inserted; and

FIG. 3d is a perspective view of the first article of footwear and thelast.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIG. 1 and FIGS. 3a to 3d, there is shown a lastgenerally indicated at 10 according to the invention. The last 10comprises a cast in the form of a front cast 12, an end piece in theform of a heel cast 15 and fixing means in the form of resilient meansas a compression spring 18. The front cast 12 has a shaped surface 13and a rear face 14. The heel cast 15 has a shaped surface 16, a frontface 17 and a top face 19. In FIG. 1, the compression spring 18 isillustrated in a compressed state.

The front cast 12 of the last 10 according to the invention ismanufactured by lining the internal surface of the front end of a secondarticle of footwear with a non-permeable material, for example latexrubber, polythene or the like. A second article of footwear, which hasbeen pre-shaped by an individual's foot through wear, is a particularlysuitable article of footwear for this purpose.

The lining is filled with a liquid, for example, polyester resin,although any suitable castable liquid 34 may be employed. The liquid iscaused to substantially harden, for example by curing, to form the frontcast 12 which is then removed from the second article of footwear 30.

It will be understood that the front end of the second article offootwear 30 refers to the area substantially from the instep to the toeof that article of footwear.

The heel cast 15 is formed by repeating the above-mentioned processusing the internal surface of the opposite or heel end of the secondarticle of footwear or shoe.

The last 10 according to the invention is constructed by fixing the rearface 14 of the front cast 12 to the front face 17 of the heel cast 15using the resilient means or compression spring 18.

A number of conventional methods may be used to fix the spring 18between the front cast 12 and the heel cast 15. For example, each end ofthe spring 18 may be inserted into the front or rear cast 12, 15,respectively before they fully harden, allowing each cast 12, 15 topositively engage the spring 18 once hardened. Alternatively, the frontand rear faces 17, 14 of the casts 15, 12, respectively, can be threadedto allow the spring 18 to be screwed into each cast 12, 15. Depending onthe nature of the castable liquid used to form the casts 12, 15, it maybe possible to adapt each end of the spring 18 to self thread into eachof the front or rear faces 17, 14 of the casts 15, 12 respectively.

The length of the spring 18 is determined by the length of theindividual's foot. The length of the spring 18 is chosen so that, whenthe spring 18 is substantially fully but, not completely, extended, thelast 10 fits fully along the length of the individual's first article offootwear 36, from heel to toe.

Typically, a compression spring with a half inch bore is suitable forconnecting the casts 12, 15. It will be appreciated that the purpose ofthe compression spring 18 is to urge the front cast 12 and the heel cast15 into engagement with the front end and heel end, respectively, of thefirst article of footwear 36 and that, accordingly, the compressionspring 18 could be replaced by any alternative conventional fixing meansadapted to urge each end of the last 10 into engagement with each end ofthe first article of footwear, for example, an extendable bar (notshown).

It will be appreciated that, for each shoe of a pair of first articlesof footwear, a last 10 according to the present invention must be madefrom the respective shoe of a pair of second articles of footwear, mostpreferably, a pair of shoes pre-worn by that individual.

Referring now to FIG. 2, there is shown a last generally indicated at20. The last 20 comprises a front cast 22, a heel cast 25 and resilientmeans in the form of a compression spring 28. The front cast 22 has ashaped surface 23 and a rear face 24. The heel cast 25 has a shapedsurface 26, a front face 27 and a top face 29. In FIG. 2, thecompression spring 28 is illustrated in a compressed state.

The front cast 22 of the last 20 is manufactured by lining the externalsurface of the front end of an individual's foot (not shown) withfibreglass (not shown) or any other material suitable for forming amould. The fibreglass or the like material is caused to harden by theapplication of an appropriate curing agent, thus forming a mould (notshown) of the front end of the foot. The mould is then removed from thefoot.

The mould is filled with a castable liquid (not shown), for example,polyester resin. The liquid is caused to substantially harden, bycuring, for example, to form the front cast 22 which is then removedfrom the mould.

It will be understood that the front end of the foot refers to the areasubstantially from the instep to the toes of that foot.

The heel cast 25 is formed by repeating the process using the externalsurface of the heel area of the foot (not shown) to form the mould andthen forming a cast using the mould.

The last 20 is constructed by connecting the rear face 24 of the frontcast 22 to the front face 27 of the heel cast 25 using the compressionspring 28. The length of the spring 28 and its compression propertiesare selected, and the spring 28 is connected between the front and heelcasts 22, 25, in the manner described above in relation to the FIG. 1embodiment.

The shaped surfaces 13, 23 and 16, 26 are thus customised or contouredto conform to the shape of the front and heel ends respectively, of theindividual's foot. In this connection, it should be noted that the last20 conforms to the shape of the individual's foot more accurately thanthe last 10.

In use, a last 10 or 20, is inserted into a first article of footwearsuch as a shoe of an unworn pair of shoes. Initially, the front cast 12,22 of the last 10, 20 might not fit fully into the front end of theunworn shoe, causing compression in the spring 18, 28. Similarly, therear casts 15, 25 of the last 10, 20 might not fit fully into the rearor heel end of the unworn shoe. However, the force exerted by thecompressed spring 18, 28 gradually pushes the front cast 12, 22 fullyinto the front end of the shoe and the rear cast 15, 25 fully into therear end of the shoe. The last 10, 20 thus fits entirely along thelength of the shoe, from heel to toe.

In this position, the shaped surfaces 13, 23 and 16, 26 exert pressureon the front and heel areas, respectively, of the unworn shoe. Thesepressures are substantially similar to the pressures which would beexerted by an individual's foot.

An unworn shoe can thus be customised or specifically shaped to suit theshape of an individual's foot, thereby alleviating the discomfort whichmust be endured when breaking-in an unworn pair of shoes.

It will be appreciated that end pieces or rear casts 15, 25 need notnecessarily conform to the heel end of the individual's foot but must,in any event, be adapted to engage, in use, the first article offootwear so that the front cast 12, 22 is urged into engagement with thefront end of the first article of footwear under the influence of theresilient means or compression spring 18, 28. Thus, or example, if aparticular individual encounters discomfort in breaking in only thefront ends of shoes, customised rear casts 15, 25 can be dispensed with.Similarly, if a particular individual encounters discomfort in breakingin only the heel ends of shoes, customised rear casts 15, 25 should beformed and the end pieces or front casts 12, 22 need not be customisedas described above but must, in any event, be adapted to engage, in use,the first article of footwear so that the rear cast 15, 25 is urged intoengagement with the rear end of the first article of footwear under theinfluence of the resilient means or compression spring 18, 28. Thus theterms "cast" and "end piece" as used herein are to be usedinterchangably and are each intended to embrace the front and heel areasof the individual's foot.

It will also be appreciated that the last 10, 20 according to theinvention facilitates a shoe-maker in making, shaping and/or repairingarticles of footwear customised or specifically shaped to suit the shapeof an individual's foot.

I claim:
 1. A method of manufacturing a last for a first article offootwear, the last comprising a cast shaped and dimensioned tocustomize, in use, one end of the first article of footwear for one endof an individual's foot; and an end piece adapted to engage, in use, theopposite end of the first article of footwear, said method comprisingthe steps of customizing the cast for said one end of the individual'sfoot; and fixing the cast to the end piece characterized in that thecustomizing step comprises lining the internal surface of one end of asimilar sized second article of footwear; substantially filling thelining with a material which is suitable for forming the cast; andremoving the resulting cast.
 2. A method according to claim 1, in whichthe lining is formed from latex rubber.
 3. A method according to claim 1or 2, in which the end piece is formed by lining the internal surface ofthe opposite end of the second article of footwear; substantiallyfilling the lining with a castable material; and removing the resultingcast.